Space Plane

The in-universe replacement to the Space Shuttle. There were two versions: a low earth orbit, fully-reusable replacement for Shuttle, and an advanced version, being used to test more advanced propulsion systems. The hope was to eventually develop an interstellar drive, but after a nearly-disastrous accident that nearly destroyed the Kitty Hawk -- the mission on which Dr. Megan McAllister was to have flown, with disaster only averted by Alpha One's intervention -- the advanced space plane project was put on hold. NASA believed that the pilot of the space plane, Scott Chadwick, died in the accident, and this resulted in a re-evaluation of the project. In reality, Chadwick, who was close friends with McAllister, decided to leave NASA and join the Agency.